A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

Claire and Rupert Callender of the Green Funeral Company pose for a photograph with a environmentally friendly coffin in woodland close to their office at Dartington Hall Estate on February 4, 2011 near Torquay, England. The Devon-based company operates as funeral directors and undertakers throughout the South West, offers an ecological alternative to traditional funerals, with coffins made from ecologically friendly materials such as wicker and bamboo, and can arrange funerals that encompass diverse religious and spiritual beliefs everything from a Catholic Requiem Mass, to a Pagan ritual at a stone circle on Bodmin Moor. (Photo by Matt Cardy/Getty Images)

Among the fish populations that could be harmed by the Xayaburi dam in Laos is the critically endangered Mekong giant catfish, considered by the Guinness Book of World Records to be the world’s largest freshwater fish. The fish, which grows to 650 pounds and about 10 feet long, is only found in the Mekong River. It is migratory, moving between downstream habitats in Cambodia upstream to northern Thailand and Laos each year to spawn. Some experts fear the Xayaburi dam could block the migration and drive the giant catfish to extinction. (Photo by Courtesy of Zeb Hogan/University of Nevada, Reno)

Early morning storms over the Masai Mara National Reserve, Kenya on August 26, 2016. (Photo by Action Press/Rex Features/Shutterstock)

A brown bear waits for food at the zoo in Madrid, Spain on July 30, 2016. (Photo by Jorge Sanz/Pacific Press/SIPA Press/Rex Features/Shutterstock)

Japanese macaque monkeys enjoy sitting in the hot springs at Jigokudani-Onsen (Hell Valley) on January 23, 2005 in Jigokudani, Nagano-Prefecture, Japan. Japanese Macaques, also known as snow monkeys are the most northerly nonhuman primate in the world. In 1963 a female Macaque ventured into the hot springs to retrieve some soybeans. This behaviour was adopted by other monkeys, and eventually by the entire troop. This Macaque troop regularly visits the Jigokudani-Onsen springs to escape the cold. The hot springs are said to help relieve nerve pain and fatigue. (Photo by Koichi Kamoshida/Getty Images)

Artists wearing Japanese traditional clown masks march during the First Konpira Festival at Kotohiragu shrine in Tokyo Wednesday, January 10, 2018. The shrine is dedicated to sailors and seafaring. (Photo by Eugene Hoshiko/AP Photo)

Aerial view over mud and waste from the disaster caused by dam spill in Brumadinho, Minas Gerais, Brazil, 26 January 2019. At least nine people have died and 300 are missing after a tailings dam burst at the Feijao mine in southeastern Brazil owned by Vale, the world's largest iron-ore producer, the Minas Gerais state government said. The dam in Brumadinho near Belo Horizonte broke on 25 January at around mid-day, unleashing a river of sludge that destroyed some nearby houses. (Photo by Antonio Lacerda/EPA/EFE)